Trepan

I’ll stick with the leeches, thanks.

Dear Word Detective: I was reading a novel the other day that referred to one of the characters as having been “trepanned.” I was confused, because my understanding was that the word referred to drilling holes in something, often a skull, and I seemed to have missed the scene where the guy got his skull perforated. An obligatory search of Dictionary.com revealed that there is a secondary meaning of “trepan” as a verb — to trick or swindle — and, as a noun, — one who does the tricking or swindling — implying that one who is “trepanned” is one who has been tricked or swindled (something that made far more sense in the context of my novel than having holes bored in one’s head). My question, then, is this: are these two terms related? If so, what is the logic there, and if not, what is the origin of the latter definition? — Gwyn.

Well, I hope they’re not the same word, simply because I’ve always had a secret gnawing dread of having holes drilled in my noggin and would prefer not to have to think about it.

As it turns out, the “trepan” that refers to drilling holes in your head and the “trepan” which means “to swindle” (or the person or trick involved in a swindle) are not the same word, and there’s no real connection between the two words. Except maybe a little.

The earlier of the “trepans” to appear in English was the “hole in the head” one, around 1400. The noun “trepan,” from which the verb was formed, is defined as “a surgical saw for cutting out pieces of bone, especially from the skull,” and was derived, via French, from the Greek “trypan,” meaning “to bore.” “Trepan” as a noun has also been used to mean a contraption used to bore holes in the walls of fortresses under siege, as well as a shaft used to drill holes in the ground for a variety of purposes. The associated verb “to trepan,” meaning “to bore through bone, particularly the skull” appeared at about the same time (“Prince Rupert is … so bad, that he doth now yield to be trapan’d,” Diary, Samuel Pepys, 1667). “Trepan” has also been used since the early 20th century to mean “to bore a hole through something (wood, metal, etc.) so as to remove a core in one piece” (“The smaller holes are best bored, but large holes can be trepanned in order to save a useful piece of material,” 1970).

“Trepan” in the “hoodwink” sense first appeared as criminal underworld slang in the mid-17th century both as a noun (meaning both “someone who tricks or traps victims” and the trick or trap itself) and as a verb meaning “to ensnare, beguile, cheat” (“Ten of those Rogues had trapann’d him out of 500 Crowns,” 1662). As you can see from that 1662 quotation, the original spelling of this “trepan” was “trapan,” and the most likely explanation of the word is that “trapan” was simply derived from the verb “to trap.” So, in origin, the two “trepans” are completely separate words.

Now things get a little weird. The later change in the spelling of “trapan” to “trepan” may have arisen at least in part because “trepan” in the “bore a hole in your head” sense was a far more well-known word than “trapan,” which was fairly obscure thieves’ slang. (It also probably didn’t help that “trepan” in the “bore” meaning was, at that time, occasionally spelled “trapan.”) The Oxford English Dictionary also suggests that the switch from the spelling “trapan” to “trepan” occurred because people thought “trapan” must be a figurative use of “trepan,” i.e., that people who were beguiled or cheated were metaphorically being “bored into” by the con artist. That apparently made so much sense to so many people that both words are now spelled “trepan.”